1. Field of the Invention
The invention relates to a touch device, and more particularly to an optical touch device.
2. Description of the Related Art
Referring to FIG. 1, a conventional optical detection system disclosed in Taiwanese Patent Application Publication No. 201035836 is shown to include a scanning device 110, a linear sensor 120, and a distinguishing unit 130. The scanning device 110 includes a light source 112, a mirror 114, and a rotating actuator 116. The light source 112 is operable to generate a scan light beam. The mirror 115 is positioned to direct the scan light beam into a detection region 140. The rotating actuator 116 is coupled to the mirror 114 for rotating the mirror 114 and thereby varying an incident angle of the scan light beam with time. The linear sensor 120 is positioned to sense two reflected scan light beams 610, 620 respectively generated due to reflection of the scan light beam by two actual touches (T1, T2) within the detection region 140. The distinguishing unit 130 is operable to distinguish the actual touches (T1, T2) from two ghost touches (G1, G2) according to time signals which respectively indicate the times that the reflected scan light beam 610, 620 are sensed by the sensor 120.
However, for such a configuration, the locations of the actual touches (T1, T2) are determined according to the incident angles of the reflected scan light beams 610, 620 by way of triangulation, in which involves relatively complicated computation.